// script.aculo.us slider.js v1.8.1, Thu Jan 03 22:07:12 -0500 2008

// Copyright (c) 2005-2007 Marty Haught, Thomas Fuchs 
//
// script.aculo.us is freely distributable under the terms of an MIT-style license.
// For details, see the script.aculo.us web site: http://script.aculo.us/

if (!Control) var Control = { };

// options:
//  axis: 'vertical', or 'horizontal' (default)
//
// callbacks:
//  onChange(value)
//  onSlide(value)
Control.Slider = Class.create({
    initialize: function(handle, track, options)
    {
        var slider = this;

        if (Object.isArray(handle))
        {
            this.handles = handle.collect(function(e)
            {
                return $(e)
            });
        }
        else
        {
            this.handles = [$(handle)];
        }

        this.track = $(track);
        this.options = options || { };

        this.axis = this.options.axis || 'horizontal';
        this.increment = this.options.increment || 1;
        this.step = parseInt(this.options.step || '1');
        this.range = this.options.range || $R(0, 1);

        this.value = 0; // assure backwards compat
        this.values = this.handles.map(function()
        {
            return 0
        });
        this.spans = this.options.spans ? this.options.spans.map(function(s)
        {
            return $(s)
        }) : false;
        this.options.startSpan = $(this.options.startSpan || null);
        this.options.endSpan = $(this.options.endSpan || null);

        this.restricted = this.options.restricted || false;

        this.maximum = this.options.maximum || this.range.end;
        this.minimum = this.options.minimum || this.range.start;

    // Will be used to align the handle onto the track, if necessary
        this.alignX = parseInt(this.options.alignX || '0');
        this.alignY = parseInt(this.options.alignY || '0');

        this.trackLength = this.maximumOffset() - this.minimumOffset();

        this.handleLength = this.isVertical() ? (this.handles[0].offsetHeight != 0 ? this.handles[0].offsetHeight :
                                                 this.handles[0].style.height.replace(/px$/, "")) :
                                                (this.handles[0].offsetWidth != 0 ? this.handles[0].offsetWidth :
                                                 this.handles[0].style.width.replace(/px$/, ""));

        this.active = false;
        this.dragging = false;
        this.disabled = false;

        if (this.options.disabled) this.setDisabled();

    // Allowed values array
        this.allowedValues = this.options.values ? this.options.values.sortBy(Prototype.K) : false;
        if (this.allowedValues)
        {
            this.minimum = this.allowedValues.min();
            this.maximum = this.allowedValues.max();
        }

        this.eventMouseDown = this.startDrag.bindAsEventListener(this);
        this.eventMouseUp = this.endDrag.bindAsEventListener(this);
        this.eventMouseMove = this.update.bindAsEventListener(this);

    // Initialize handles in reverse (make sure first handle is active)
        this.handles.each(function(h, i)
        {
            i = slider.handles.length - 1 - i;
            slider.setValue(parseFloat((Object.isArray(slider.options.sliderValue) ? slider.options.sliderValue[i] :
                                        slider.options.sliderValue) || slider.range.start), i);
            h.makePositioned().observe("mousedown", slider.eventMouseDown);
        });

        this.track.observe("mousedown", this.eventMouseDown);
        document.observe("mouseup", this.eventMouseUp);
        document.observe("mousemove", this.eventMouseMove);

        this.initialized = true;
    },
    dispose: function()
    {
        var slider = this;
        Event.stopObserving(this.track, "mousedown", this.eventMouseDown);
        Event.stopObserving(document, "mouseup", this.eventMouseUp);
        Event.stopObserving(document, "mousemove", this.eventMouseMove);
        this.handles.each(function(h)
        {
            Event.stopObserving(h, "mousedown", slider.eventMouseDown);
        });
    },
    setDisabled: function()
    {
        this.disabled = true;
    },
    setEnabled: function()
    {
        this.disabled = false;
    },
    getNearestValue: function(value)
    {
        if (this.allowedValues)
        {
            if (value >= this.allowedValues.max()) return(this.allowedValues.max());
            if (value <= this.allowedValues.min()) return(this.allowedValues.min());

            var offset = Math.abs(this.allowedValues[0] - value);
            var newValue = this.allowedValues[0];
            this.allowedValues.each(function(v)
            {
                var currentOffset = Math.abs(v - value);
                if (currentOffset <= offset)
                {
                    newValue = v;
                    offset = currentOffset;
                }
            });
            return newValue;
        }
        if (value > this.range.end) return this.range.end;
        if (value < this.range.start) return this.range.start;
        return value;
    },
    setValue: function(sliderValue, handleIdx)
    {
        if (!this.active)
        {
            this.activeHandleIdx = handleIdx || 0;
            this.activeHandle = this.handles[this.activeHandleIdx];
            this.updateStyles();
        }
        handleIdx = handleIdx || this.activeHandleIdx || 0;
        if (this.initialized && this.restricted)
        {
            if ((handleIdx > 0) && (sliderValue < this.values[handleIdx - 1]))
                sliderValue = this.values[handleIdx - 1];
            if ((handleIdx < (this.handles.length - 1)) && (sliderValue > this.values[handleIdx + 1]))
                sliderValue = this.values[handleIdx + 1];
        }
        sliderValue = this.getNearestValue(sliderValue);
        this.values[handleIdx] = sliderValue;
        this.value = this.values[0]; // assure backwards compat

        this.handles[handleIdx].style[this.isVertical() ? 'top' : 'left'] = this.translateToPx(sliderValue);

        this.drawSpans();
        if (!this.dragging || !this.event) this.updateFinished();
    },
    setValueBy: function(delta, handleIdx)
    {
        this.setValue(this.values[handleIdx || this.activeHandleIdx || 0] + delta, handleIdx || this.activeHandleIdx
                || 0);
    },
    translateToPx: function(value)
    {
        return Math.round(((this.trackLength - this.handleLength) / (this.range.end - this.range.start)) * (value
                - this.range.start)) + "px";
    },
    translateToValue: function(offset)
    {
        return ((offset / (this.trackLength - this.handleLength) * (this.range.end - this.range.start))
                + this.range.start);
    },
    getRange: function(range)
    {
        var v = this.values.sortBy(Prototype.K);
        range = range || 0;
        return $R(v[range], v[range + 1]);
    },
    minimumOffset: function()
    {
        return(this.isVertical() ? this.alignY : this.alignX);
    },
    maximumOffset: function()
    {
        return(this.isVertical() ?
               (this.track.offsetHeight != 0 ? this.track.offsetHeight : this.track.style.height.replace(/px$/, ""))
                       - this.alignY :
               (this.track.offsetWidth != 0 ? this.track.offsetWidth : this.track.style.width.replace(/px$/, ""))
                       - this.alignX);
    },
    isVertical:  function()
    {
        return (this.axis == 'vertical');
    },
    drawSpans: function()
    {
        var slider = this;
        if (this.spans)
            $R(0, this.spans.length - 1).each(function(r)
            {
                slider.setSpan(slider.spans[r], slider.getRange(r))
            });
        if (this.options.startSpan)
            this.setSpan(this.options.startSpan, $R(0, this.values.length > 1 ? this.getRange(0).min() : this.value));
        if (this.options.endSpan)
            this.setSpan(this.options.endSpan, $R(this.values.length > 1 ? this.getRange(this.spans.length - 1).max() :
                                                  this.value, this.maximum));
    },
    setSpan: function(span, range)
    {
        if (this.isVertical())
        {
            span.style.top = this.translateToPx(range.start);
            span.style.height = this.translateToPx(range.end - range.start + this.range.start);
        }
        else
        {
            span.style.left = this.translateToPx(range.start);
            span.style.width = this.translateToPx(range.end - range.start + this.range.start);
        }
    },
    updateStyles: function()
    {
        this.handles.each(function(h)
        {
            Element.removeClassName(h, 'selected')
        });
        Element.addClassName(this.activeHandle, 'selected');
    },
    startDrag: function(event)
    {
        if (Event.isLeftClick(event))
        {
            if (!this.disabled)
            {
                this.active = true;

                var handle = Event.element(event);
                var pointer = [Event.pointerX(event), Event.pointerY(event)];
                var track = handle;
                if (track == this.track)
                {
                    var offsets = Position.cumulativeOffset(this.track);
                    this.event = event;
                    this.setValue(this.translateToValue((this.isVertical() ? pointer[1] - offsets[1] :
                                                         pointer[0] - offsets[0]) - (this.handleLength / 2)));
                    var offsets = Position.cumulativeOffset(this.activeHandle);
                    this.offsetX = (pointer[0] - offsets[0]);
                    this.offsetY = (pointer[1] - offsets[1]);
                }
                else
                {
                    // find the handle (prevents issues with Safari)
                    while ((this.handles.indexOf(handle) == -1) && handle.parentNode)
                        handle = handle.parentNode;

                    if (this.handles.indexOf(handle) != -1)
                    {
                        this.activeHandle = handle;
                        this.activeHandleIdx = this.handles.indexOf(this.activeHandle);
                        this.updateStyles();

                        var offsets = Position.cumulativeOffset(this.activeHandle);
                        this.offsetX = (pointer[0] - offsets[0]);
                        this.offsetY = (pointer[1] - offsets[1]);
                    }
                }
            }
            Event.stop(event);
        }
    },
    update: function(event)
    {
        if (this.active)
        {
            if (!this.dragging) this.dragging = true;
            this.draw(event);
            if (Prototype.Browser.WebKit) window.scrollBy(0, 0);
            Event.stop(event);
        }
    },
    draw: function(event)
    {
        var pointer = [Event.pointerX(event), Event.pointerY(event)];
        var offsets = Position.cumulativeOffset(this.track);
        pointer[0] -= this.offsetX + offsets[0];
        pointer[1] -= this.offsetY + offsets[1];
        this.event = event;
        this.setValue(this.translateToValue(this.isVertical() ? pointer[1] : pointer[0]));
        if (this.initialized && this.options.onSlide)
            this.options.onSlide(this.values.length > 1 ? this.values : this.value, this);
    },
    endDrag: function(event)
    {
        if (this.active && this.dragging)
        {
            this.finishDrag(event, true);
            Event.stop(event);
        }
        this.active = false;
        this.dragging = false;
    },
    finishDrag: function(event, success)
    {
        this.active = false;
        this.dragging = false;
        this.updateFinished();
    },
    updateFinished: function()
    {
        if (this.initialized && this.options.onChange)
            this.options.onChange(this.values.length > 1 ? this.values : this.value, this);
        this.event = null;
    }
});
